Compressor



Nm 4, 1941. H. A. FELDBUSH 2,253,241

COMPRESSOR Filed March 15, 1959 2 Sheets-Sheet l HARRY A. FaLosusu INVENTOR ATTORNEY- Nov. 4, 1941. H. A. FELDBUSH COMPRESSOR Filed March 15, 1939 2 Sheets-Sheet 2 v HARRY A.'-Faa.0ausu INVENTOR ATTORNEY Patented Nov. 4, 1941 commasson mm A. Feldbush, sum Hills, N.- 1., assignor to Machin' Worthington Pump and cry Corporation, Harrison, N. J.,' corporation of Delaware Application March 15, 1939, S erialNo. 261,882

1 Claim. (01,230-203) the evacuating compressor connected in the sys- This invention relates to compressors and more particularly to a compressor for use in a refrigerating system for handling a refrigerant such as Freon, ammonia, etc. In'compressors handling a refrigerant such as .Freon".or the like it is extremely difiicult if not impossible to prevent the leakage of the refrigerant from the cylinder along the piston rod, particularly since such refrigerants are soluble in lubricating oil.

The refrigerant leakage being subjected to atmospheric pressure when it leaves the compressor 7 cylinder immediately becomes gas and escapes,

being unrecoverable and resulting in loss of refrigerant as well as in some instances causing an undesirable odor and polution of the air in the compressor room. Since the loss of the refrigerant due to such leakage, over an extended period, is considerable, it is desirable froman economical standpoint to prevent the dissipation of such refrigerant and return it to the refrigerating system. i

It is an object of the present invention to provide a method and apparatus whereby the leak- Figure 2 is a vertical section taken onthe line 2--2 through a compressor constructed in accordance with thepresent invention.

Referring more particularly to the drawings; a

duplex double-acting compressor'for compressing Freon, ammonia or analogous refriger-- ants is shown in Figures 1- and 2 of the drawings, and comprises the cylinder block I having the compound cylinders 2 and 3 formed'thereih, .in which the pistons 4 reciprocate. The pistons 4 have piston rods 5 connected thereto-which extend through suitable packings 6 into the crank case], where theyare connected to cross-heads 8. The cross-heads 8 reciprocate on the guides 9 and are connected by connecting rods It to age of refrigerant from a-compressor to atmosphere and its resultant dissipation will be prevented, and the leakage'refrigerant will be returned to the system. More especifically, an object of the present invention is to provide in combination with a refrigerant compressor having a completely 'enclosed crank case in substantially fluid-tight connection with the compressor cylinder or cylinders which crank casereceives the refrigerant leaking from the cylinders along the piston rods, an evacuating compressor having its suction con: nected to the crank case and its'dischargeto the refrigerant system for maintaining pressure .in the crank case at approximately atmospheric pressure for recovering the vaporous or gaseous refrigerant from the crank case and returning it the crank shaft II. -The 'crankshaft Ii rotates insuitable bearings l2 and ll, carried by the,

crank case ii .of the compressor. The crank case I5 is connected in fluid-t ht connection. as shown at I8, to the cylinder block I, and the space in the interior of thelcrank case is reduced to the minimum necessary for the effective operation of the parts of the compressor therein by suitable webbing,.as shown at ii. In the present system it is desirable to have as small a space as possible within thecrank. case ofthe compressor, since this space is evacuated by a'relatively'small evacuating compressor It. The suc-v tion of the evacuating compressor i8 is connected 2 inder of thecompressor or to other suitable low pressure'points in the refrigerating system in by means of a pipe I! to the interior of the crank case It, while its discharge is connected. by means of a suitable pipe 20 either to the suction of the low pressure end of the low pressurecyl- "which the compressor is employed. A check to the system in which-the refrigerant compressor is employed.

With these and other objects in view, as may appear from the accompanyin speciflcation,,'the

invention consists of various features of construction and combination of parts, which will be first described in connection with the accompanying drawings, showing a compressor of the preferred form embodying the invention. and the features forming the invention will be specifically.

pointedout in the claim.

In, the drawings:

valve 2! is positioned in the pipe 10 to'p'revent back-flow to the evacuatingcompressor It.

A pressure actuated electric switch 22 oi any approved type, which may be purchased upon the open market, is placed in' thepipe I! so that when the pressure in the crank case it reaches a predetermined height the motor 28 which operates the evacuatingcompressor It will be started for operating the evacuating compressor to evac uate the interior of the crank case IE, or in other Figure 1 is a vertical section through a doubleecting refrigerant compressor constructed in accordance with the present invention and showing words, from the crank case I! all of the refillerant which has leaked into this crank case along the piston rods 5, and at the same time to maintain a pressure within the crank case of approximately atmospheric pressure so that the refrigerant will be in a gaseous form in the crank case i and. consequently become separated from the lubricating oil on the piston rods, which lubricating oil has served as a carrier to carry the refrigerant absorbed thereby into the crank case. When the pressure, within the crank case falls below a predetermined low pressure the pressure actuated switch structure 22 will operate to cut 01! the motor 23 and stop the operation of the evacuating compressor l8. The pipe I9 may be connected to the interior of the crank case l at any convenient point.

In Figure 1 of the drawings a branch pipe 24 is shown connected to the pipe l9 between the hand operated shut-ofi valve 25 and the evacuating compressor l8 so that it it is desired the valve 25 may be closed and the valve 26 in the branch pipe 24 opened, causing the evacuating compressor l8 to draw its suction through the branch pipe 24. The branch pipe .24 is connected through a suitable duct 2lwith a space within the packing 2B for the crank shaft H, which space is identified by the lantern gland 29. The evacuating compressor 18- drawing its suction through the packing 28 and passage 21 will draw the refrigerant through the packing or along the crank shaft H and thus to the evacuating compressor and back into the refrigerant system. If it is so desired, both of the valves 25 and 26 may be opened so that the compressor I8 will draw from both sources.

' By maintaining a pressure in the fluid tight crank case and within the bearing M'of approximately atmospheric pressure the refrigerant which leaks into the, crank case will remain in a gaseous state and will become separated from the lubricating oil so that it may be readily withdrawn by the evacuating compressor 18 and returnedto the refrigerating system, thus not only preventing its escape into the compressor room, but also resulting in the saving of the refrigerant, some types of which are quite expensive.

It will be understood that the invention is not to be limited to the specific construction -.or arrangement of parts shown, but that they may be widely modified within the invention defined by the claim.

Whatis claimed is:

In a refrigerant compressor, the combination with a compressor cylinder, 9. piston and an operating shaft for said piston, of a. sealed crank case in fluid tight connwtion with the cylinder for receiving refrigerantleakage therefrom, said shaft extending out of said crank case, a packing about said shaft, an evacuating compressor operable independently of the refrigerant compressor and having its suction connected to said packing structure to withdraw refrigerant leakage from the packing and reduce the pressure within said packing structure about the shaft to approximately atmospheric pressurefor preventing leakage of refrigerant through the packing structure, means connecting the suction of said evacuating compressor to the interior of said crank case for withdrawing gaseous refrigerant from the crank case, and pressure actuated means actuated by pressure from within said crank case for controlling operation of said evac uating compressor independently of operation of the refrigerant compressor.

HARRY A. FELDBUSH. 

